Process of manufacturing multiple-chamber inner tubes for pneumatic tires.



ALFRED RAYMOND & ALBERT RAYMOND. PROCESS OF MANUFACTURING MULTIPLECHAMBER INNER TUBES FOR. PNEUMATIC TIRES.

APPLICATION FILED 8EPT.25,1913.

1,079,186, Patented Nov. 18, 1913.

.nn srarns PATENT OFFICE.

ALFRED RAYMOND AND ALBERT RAYMOND, OF WASHINGTON, DISTRICT OF COLUMBIA.

PROCESS OF MANUFACTURING MULTIPLE-CHAMBER INNER TUBES FOR PNEUMATICTIRES.

To a l whom it may concern Be it known that we, ALFRED RAYMOND andALBERT RAYMOND, citizens of the United States, residing at Washington,District of Columbia, have invented and discovered cer tain. new anduseful Improvements in Processes of lilanufacturing Multiple- Chamber.Inner Tubes for Pneumatic Tires, of which parts as shown in Fig. l arethen placed upon a mandrel 15 of appropriate material the following is aspecification.

Our said invention consists in an improved process for manufacturingmultiple chamber inner tube structures for pneumatic tires whereby sucha structure may be formed at one operation upon a single mandrel and ina comparat vely inexpensive manner, all as will be hereinafter more fulldescribed and claimed.

Referring to the accompanying drawing which is made a part hereof and onwhich similar reference characters indicate similar parts, Figure 1 is aperspective view of the parts of which the inner tube structure iscomposed as ass mbled before winding upon the mandrel, 2 a perspectiveView of a mandrel having the various parts of which the tire is composedbound thereon in position for curing, Fig. 3 a cross-section through afinished tube, and Fig. 4 a detail perspective view illustrating themethod of splicing the ends of the tube.

Said process is carried out as follows: A sheet, A, of the raw material,as rubber, of the pro; or length and width to form a tube structure ofthe desired length and diameter, is laid flat upon a table or bench. Twosmaller tubes B and G each of a diameter equal to approximately onethird of the circumference of the tube structure as a whole, are placedupon the face of said sheet A edge to edge, as illustrated in Fig. 1.The tubes B and C are also of elastic material, as rubber, flattened,and contain, or are wrapped around, strips of substance adapted toprevent their adjacent faces from his ing or adhering. For this purposewe have used strips 10 of glazed holland but other appropriate material,or substance, may, of course, be used instead. Said strips 10 are of awidth equal to the normal diameter of tubes B and C. In order to providefor the splicing of the several tubes or chambers when formed, we alsoinsert.

other strips 11, of like material, between the ends of tubes B and C andthe ad acent face of the sheet A and in order to maintain Specificationof Letters Patent.

Application tiled September 25, 1913.

Patented Nov. 1 8,1913. Serial No. 791,830.

the ends of the tubes B and C independent of each other, a fold or part12 of such material projects upward between their adjacent edges at eachend. Said strips 11 with the parts 12 are of equal width, approximatelyfivo or six inches, or whatever length may be necessary to form anapproximate splice between the parts. The several and hollow, the edgesof the sheet A overlapping as at at. A stri D of raw material of a Widthadapted to fi l the space between the outer edges of tubes B and G, isplaced upon the outside of the sheet A in appropriate position to fillsaid space, being of the requisite thickness. The whole is then boundupon said mandrel under pressure by winding tightly a strip E of bindingmaterial, such as glazed holland, or other noI-i-adliesivc fabric,around the exterior thereof, which serves to force the strip D into therecess between the edges of tubes B and C forming a substantially evenexterior surface, and a tube structure of substantially uniformthickness throughout its circumference. The inaudrels thus prepared arethen introduced into an oven heated to appropriate temperature, and therubber, or raw material of other character found appropriate, is heatedto a fusing point, under which heat the outer faces of tubes 13 and Ofuse with the inner face of the sheet A and the overlapping edges ofsaid sheet A fuse together and the filling strip D fuses with theoutside surface of sheet A, thus forming a complete tube structure ofuniform thickness throughout its circumference, and a tube structurewherein a multiplicity of chambers are provided, one by the outside tubeA and two others by the tubes B and C, the walls of which are kept fromfusing by the strips 10 as before described.

After the tube structure has cured it is stripped from the mandrel, thestrips 10, 11, and 12, withdrawn, leaving a tube of appro priate lengthwith the several chambers fused together except for a distance at eachend. and said ends free from each other. In the. splicing operation thefree ends of the tube A are turned back, as shown in Fig. 4;, leavingthe free ends of tubes 13 and C projecting beyond the end of tube A.Tubes B and C are then spliced successively This method is illustratedin Fig. i, whereand independently, in the manner ordi narily employedfor the splicing of tubes, consisting of turning back one end, spreadingthe cement upon the other end, bringing'the ends together, and thenturning forward the turned back end upon the cemented exterior surfaceof the complementary projecting end, which may be held distended, orexpanded, by turning in a moderate air pressure after the ends have beenfirst brought together and continuing the pressure until the splice iscomplete.

in one inner tube is shown with the splice complete, the other is readyfor splicing, and the free ends of tube A are turned back out of theway, butmay be spliced in the same manner after both inner tubes arespliced.

It will be understood, of course, that patches of glazed hollandf orother suitable material, may be placed between the tubes at the point,or points, where valves are to be inserted in order to preserve suitablespace for the connection. It will also be understood that the tubes Band C may be formed before assembling with the sheet A, or maythemselves be sheets of appropriate dimensions folded over the strips 10with their edges overlapping and adapted to fuse when the Wholestructure is placed in the oven on the mandrel. it will also beunderstood that the free ends of the tubes B and C left for splicingpurposes, may be secured to the inner surface of the tube A by placingcement on the appropriate portion of their surfaces and introducingsuliicient air pressure to flatten said portions against said tube Auntil adhesion results In removing the glazed holland from Within thetubes B and C, I have found it helpful to force Water through the tubes,which releases the fabric and permits it to be easily withdrawn by hand,

The method of construction above described will provide an inner tubestructure with its rough or wrapped side on the outside face when inuse. In order to'o-btain a smooth exterior, as is in some cases desired,it will be necessary to reverse the process or building upon themandrel, that is, first Wrapping the mandrel with the single sheet ofstock, then applying the tubes constructed upon the strips of holland,adding the thickening strip, and binding the whole upon the mandrel, andafter curing turning the structure inside out.

The method above described may be modified in other particulars so faras details are concerned without departing from our said invention.

Having thus fully described our said invention what We claim as new anddesire to secure by Letters Patent is:

1. The process of manufacturing multiple chamber rubber tubes whichconsists in arranging a series of tubes on the surface of a sheet ofmaterial from which an outer tube is to be formed, inserting within saidinner tubes substance of a character to prevent adhesion of the adjacentsurfaces, winding the whole upon a mandrel and subjecting to heatsul'iicient to fuse the several parts together, substantially as setforth.

2. The process 01"" manufacturing multiple chamber rubber tubescomprising placing a series of small tubes containing cores ofnonadhesive material on a sheet of material of dimensions requisite toform the large tube, placing a strip of thickening material betweenadjacent edges of said smaller tubes, binding the several parts upon themandrel and subjecting the whole to heat until the several parts fusetogether, substantially as set forth.

8. The process of manufacturing multiple chamber inner tubes forpneumatic tires comprising arranging a series of smaller tubes withtheir inner faces separated by non-adhetive substance and a sheet ofmaterial. of dimensions requisite to form a large tube upon a mandrel,placing a strip of thickening material in the space between the edges ofthe smaller tubes, binding the whole to the mandrel, and subjecting itto heat suthcient to fuse the several parts together, substantially asset forth.

l. The process of manufacturing multiple chamber inner tubes'ferpneumatic tires comprising arranging a series of smallertubes with theirinner faces separated by nonndhesive substance and a sheet of materialto form the large tube upon a mandrel, the ends of said sheet and theends of said tubes being also separated by a nonadhesive substance,binding the whole to a mandrel, fusing the parts together, and thensplicing the ends of'the separate tubes, substantially as set forth.

In witness whereof, we have hereunto set our hands and seals at Akron,Ohio, this 24th day of September, A. D, nineteen hundred and thirteen. v

ALFRJIED RAYMOND. [1 s1. AL-Blltl RAYMUND. [n1 s] -l fitnesses l damnGAULT, Cennrn D. Knnorrr.

llopies of this patent may be obtained for five cents each, byaddressing; the @oinmissioner of Patents,

l ll ashington, ill, *3,

